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Simple tests for density functional methods
Author(s) -
Csonka Gábor I.,
Nguyen Nam Anh,
Kolossváry István
Publication year - 1997
Publication title -
journal of computational chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.907
H-Index - 188
eISSN - 1096-987X
pISSN - 0192-8651
DOI - 10.1002/(sici)1096-987x(199709)18:12<1534::aid-jcc10>3.0.co;2-k
Subject(s) - simple (philosophy) , density functional theory , perturbation theory (quantum mechanics) , hybrid functional , statistical physics , perturbation (astronomy) , electron density , computational chemistry , chemistry , mathematics , thermodynamics , quantum mechanics , physics , electron , philosophy , epistemology
The performance of the currently used generalized gradient approximation density functionals is analyzed using several simple, yet critical requirements. We analyze the effects of the self‐interaction error, the inclusion of the exact exchange, and the parameter settings used in the popular three‐parameter hybrid density functionals. The results show that the elimination of the self‐interaction error from the current density functionals lead to very poor results for H 2 . The inclusion of the exact exchange does not significantly influence the self‐interaction corrected results. The variation of the A , B , and C parameters of a hybrid DFT method influences the H(SINGLE BOND)H equilibrium bond length through a very simple linear equation, and it is possible to reproduce the experimental H(SINGLE BOND)H distance with appropriate selection of these parameters, although an infinite number of solutions exists. Similar results were obtained for the total energy and the electron density along the internuclear axis. The analysis of the exact KS potential at the bond critical point of the dissociating H 2 molecule shows that, for this property, the second order Moller–Plesset perturbation theory yields a better potential than the density functionals studied in this article. © 1997 John Wiley & Sons, Inc. J Comput Chem 18 : 1534–1545, 1997